// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "media/cdm/simple_cdm_allocator.h"

#include "base/bind.h"
#include "base/memory/ptr_util.h"
#include "media/base/video_frame.h"
#include "media/cdm/cdm_helpers.h"
#include "media/cdm/simple_cdm_buffer.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/geometry/size.h"

namespace media {

namespace {

    class SimpleCdmVideoFrame : public VideoFrameImpl {
    public:
        SimpleCdmVideoFrame() { }
        ~SimpleCdmVideoFrame() final { }

        // VideoFrameImpl implementation.
        scoped_refptr<media::VideoFrame> TransformToVideoFrame(
            gfx::Size natural_size) final
        {
            DCHECK(FrameBuffer());

            cdm::Buffer* buffer = FrameBuffer();
            gfx::Size frame_size(Size().width, Size().height);
            scoped_refptr<media::VideoFrame> frame = media::VideoFrame::WrapExternalYuvData(
                PIXEL_FORMAT_YV12, frame_size, gfx::Rect(frame_size), natural_size,
                Stride(kYPlane), Stride(kUPlane), Stride(kVPlane),
                buffer->Data() + PlaneOffset(kYPlane),
                buffer->Data() + PlaneOffset(kUPlane),
                buffer->Data() + PlaneOffset(kVPlane),
                base::TimeDelta::FromMicroseconds(Timestamp()));

            // The FrameBuffer needs to remain around until |frame| is destroyed.
            frame->AddDestructionObserver(
                base::Bind(&cdm::Buffer::Destroy, base::Unretained(buffer)));

            // Clear FrameBuffer so that SimpleCdmVideoFrame no longer has a reference
            // to it.
            SetFrameBuffer(nullptr);
            return frame;
        }

    private:
        DISALLOW_COPY_AND_ASSIGN(SimpleCdmVideoFrame);
    };

} // namespace

SimpleCdmAllocator::SimpleCdmAllocator() { }

SimpleCdmAllocator::~SimpleCdmAllocator() { }

// Creates a new SimpleCdmBuffer on every request. It does not keep track of
// the memory allocated, so the caller is responsible for calling Destroy()
// on the buffer when it is no longer needed.
cdm::Buffer* SimpleCdmAllocator::CreateCdmBuffer(size_t capacity)
{
    if (!capacity)
        return nullptr;

    return SimpleCdmBuffer::Create(capacity);
}

// Creates a new SimpleCdmVideoFrame on every request.
std::unique_ptr<VideoFrameImpl> SimpleCdmAllocator::CreateCdmVideoFrame()
{
    return base::MakeUnique<SimpleCdmVideoFrame>();
}

} // namespace media
